The shackleless padlock has been widely used to prevent unlawful access. Various shackleless locks are illustrated and described in Randel U.S. Pat. No. 3,769,821 issued Nov. 6, 1973, entitled "Lock Device for Securing Apertured Members"; Randel U.S. Pat. No. 3,817,062 issued Jun. 18, 1974, entitled "Lock Device for Securing an Apertured Member"; and Siegel U.S. Pat. No. 4,754,626, issued Jul. 5, 1988, entitled "Shackleless Lock Protector." Typically, the shackleless lock is used with a hasp type arrangement on adjoining doors or a door contiguous to a fixed wall to prevent unwanted access beyond the door or doors.
In such prior shackleless locks it has been common to provide rotation of a shaped or cam-like lock bolt with the key rotation. Often difficulty is encountered with aligning the lock bolt and passing it through the hasp staple. In addition, these prior locks typically provide for manual sliding movement of the lock plug and lock bolt with the use of the key to engage or subsequently disengage the hasp staple.
Also, conventionally, the lock body has been made from a die cast metal alloy composition to keep manufacturing costs at a minimum. However, a die cast lock body is susceptible to being cut or broken. To give the die cast lock body additional strength, hardened pins have been force fit into holes which are perpendicularly made into the rear face of the lock body at various points near the perimeter of the rear face. Unfortunately, this technique has not completely eliminated lock body breakage or penetration.